Fluid-operated drill.



L. W. GREVEU FLU) OPERATED DRILL. APPLICATION mm) AUG-9. ms.

Pammwl 10%. 4,1917.

ATTORN EYS nrrn snares raarnnr union.

LOUIS W. GREVE, O12" CLEVELAND, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TOTHE CLEVELAND ROCK DRILL COMPANY, A CORPORATION OF OHIO.

FLUID-OPERATED DRILL.

reaeaer.

Specification of Letters Patent. Patented Dec, 4, 1917.

Application filed August 9, 1.916. Serial No. 113,853.

To all whom may concern:

and useful Improvements in Fluid-0per ated Drills, of which thefollowing is a specification.

This invention relates to fluid operated drills, and particularly topneumatically op erated drills wherein the drill steel is operated byimpact of a pneumatically driven piston, and has for its principalobjects, the provision of a drilling machine wherein the drillis rotatedby the operation of the piston, the provision of a drilling machinewherein the piston rotating means is located in advance of the rear endof the piston; the provision of a rotary piston that is constructed sothat the leakage around the pistgn is reduced to a minimum thereby resulting in more perfect action of the valve;

the provision of a means for supplying fluid to the drill end whereinthe construction 1s simple and effective; the provision of a drillingmachine that is simple, effective, inexpensive and e isily assembled,and such other objects as may hereinafter appear.

lln machines wherein the piston is rotated by helical rifiing at therear end of the piston it has been found that there is considerableleakage between the rifiing grooves and the rifle nut resulting in asluggish action of the valve. To overcome this dc feet the rifiing ofth: cylinder is located in advance of the rear pressure face of thepiston so that an air-tight fit may be obtained between the piston andthe cylinder walls. Because there is no leakage the ,valve works quicklyand there is more snap to the entire operation of the machine.

lln machines wherein fluidis supplied to the drill with a tube extendingfrom the rear of the machine to the drill, considerable difficulty hasbeen experienced in securing an eft'ective inexpensiveconnection betweenthe tube and the parts through which the tube must pass in leading tothe drill, and to overcome this difliculty a rubber packing is placed onthe tube between the end of the cylinder and the fluid supply head orhandle head in such manner that it Will be compressed bothlongitudinally and laterally thereby insuring a'simple' inexpensivejoint that will not leak and may be readily assembled. Une embodiment o"the invention is illustrated in the accompanying drawings, Wh6l6l1'l- IFigure l is a longitudinal section through the drilling machine, andFig. 2 is a trans verse section on the line ll II of Fig. l.

The machine comprises a sectional cylinder 1, which is built of aplurality of sec tions secured together by bolts or other suitablemeans. These sections are the main cylinder body 2, the handle or fluidsupply casuu and the bullin late 9 secured in the enlarged bore of thechuck casing. Between the bulling plate 5) and the buthng block 5 is aratchet cage 10, 1*igs. 1 and 2,-

in which is mounted for rotation the rifle nut 11, to be hereinafterdescribed.

.lietwecn the valve block 4 and the cylinder body 2 an auxiliary blockis placed so that the auxiliary block and the valve block form acylindrical recess in which a sleeve valve 12 may reciprocatelongitudinally of the cylinder a limited distance. The inte riordiameter of the valve is the same as the dial'nctcr oi the main cylinderand comprises a continuation of the main cylinder through which thehammer piston. may operalc.

The hammer piston is provided with a reduced extension 14 which extendsforward. through the bulling block 5, rifle nut 11, bulling plate 9,into the hollowed portion 14- ot' the. chuck 7 and is adapted to impingeupon the rear end of the drill steel 15. The rear end ol the drill steelis preferably hexagonal and its into a similarly shaped opening inthefront end of the chuck and the forward movement thereof is limited bythe flexible retaining yoke 16. This yoke consists of a spring steelwire, bent to form a socket at 17 which partially surrounds the drillsteel and engages the collar 18 of the drill steel. formed into helicalsprings and terminate in straight ends 19 which pass through perforations in the extensions 20 of the chuck casing 6. Nuts 21 are.screwed uponthe ends The ends of the yoke are i of the yoke and securethe yoke against longitudinal movement. The free end of the yoke may besprung away from the drill to permit of its removal'vvhen desired.

The drill steel is provided with a central passage 22 which extends fromthe rear end of the drill to a point adjacent the pointthereof, andatube 23 extending longitudinally of the cylinder projects into the passage 22 of the drill steel. The tube 23 extends rearward through the endof the valve block and terminates in a recess 24 in the supply head orhandle 3. The rear end of the tube 23 is provided with a flange 25 whichabuts'the bottomof the recess 24, and the passage-26 of the tubecommunicates With the passage 27 in the supply head. A water tube orpipe (not shown) is screwed into the socket 28 and supplies water to thetube 23 which is conducted to the passage 22 in the drill steel. Thepiston 13 is provided with a central bore through which the. tubepasses, this bore being of suflicient size to permit of free movement ofthe piston, but is made 'so that no air may escape between the tube andthe piston.

The valve block is provided with a socket 29 opposite the socket 24 inthe head 3, and a packing 24 made of rubber or any suitable materialsurrounds the tube 23 and is incased in the sockets 24 and 29. When thehandle head 3 is drawn up tight against ple, inexpensive and easilyassembled.

The fluid chamber 31 "is provided between the handle head 3 and thevalve block 4, to serve asa storage reservoir for air immediatelyadjacent the supply ports 32 leading directly to the .valve 12. It hasbeen found that the operation of the machine is improved by having suchreservoir because a unlform supply of air is constantly delivered to thevalve and piston. Air is supplied to the fluid chamber from a hosethrough the port 33 shown in dotted lines.

Referring to Figs. 1 and 2, the piston rotating mechanism consists of arifle nut 11 surrounding the reduced extension 14 of the piston. Thepiston extension 14 is rifled with a pair of helically disposed grooves34 into which project a pair of similarly shaped ridges35 carried by therifle nut. Therefore, if the rifle nut'is held against rotation thepiston will be rotated when moves longitudinally within the cylinder bythe cooperation of the ridges 35 and the slots 34. If the rifle nut isnot held against rotation, the piston will move longitudinally of thecylinder without turning and will rotate the rifle nut.

In the operation of the machine it is preferable that the drill berotated only upon the. return stroke of the piston, so that the pistonwill be free to delivera maximum blow to thetool on its working stroke.To accomplish this operation, the rifle nut 11 is provided upon itsouter surface with a series of teeth 36 adapted to be engaged by aplurality of pawls 37 pivoted within the ratchet cage 10. The pawlsareheld in engagement with the teeth 36 by means of helical springs 38disposed in the recesses 39 bored in the ratchet cage. The awls arearranged so that they are all in ifi'erent relation with the teeth, s0that there will' always be one in position to prevent reverse movementof the rifle nut. Therefore, the rifle nut can only be rotated in thedirection indicated by the arrow. When the piston moves forward towardthe tool, the rifle grooves will cause the rifle nut to rotate in thedirection of the arrow and when the piston moves rearward the pawls 37will prevent rotation of the rifle nut, and the piston will be rotatedin the direction of the arrow.

The buffing block 5 and the ratchet cage 10 are 'held against relativemovement by a .dowel pin 37 which extends through the bufling block andprojects at one end into a recess in the ratchet cage, and projects atvthe other end into a recess in the cylinder body.

The extension 14 of the piston is also pro vided with a pair of straightgrooves 40 arranged parallel with the axis of the piston. The chuck 7 isprovided. with a pair of similarly shaped-ridges 41, Fig. 1, whichextend into the grooves 40 and prevent relative rotary motion betweenthe piston and the chuck.

Therefore, when the piston is ro tated by the action of the rifle nutthe chucke'a will rotate with it and the drill steel 15.

it will in turn rotate:

Because the valve 12, as will hereinafter be explained, is shiftedentirely by pressure in the cylinder at the rear of the piston, it isnecessary that this pressure is not reduced by leakage of air from thecylinder at the time the valve is to be shifted. For this reason therifling 0r piston rotating mechanism is placed 1n advance of the rearpressure face ot the piston so that no air can leak from behind the rearface of the piston through the rifling slots. It has been found that,

where air can escape from the rear face of the piston through riflingslots that communicate with the evlinder to the rear of the so thei,248,481 in:

is as follow vs: Air is flowing from the air I hose into the ,fiuidchamber 31 through \the .PQr 3 Ai 119W fiens t @th {i n of le s en imamit .flu d ambe rough, ts 32, ports 512 in valve blOCk,

20 'eI i1ila erbQW Qi e l-r sur i. acre ShQW- hr sag van po 1 6 Ai ise hsfi thr ushre 11M vsa 1 8; pe i fg w e as waio t e t- B sphere i lhlvave i bein hel n ea no i e shown air pressure the fluid chamber 31 suppie h ug th pa s g .52 which communicates with the fluid chamber and hasitivo ports 53 and 54: leadinginto "linder l. Rent 5 4 is now coveredvzby the a on and a r i dis har ng nt e Janna-lei" pac 55; 1 1 ghtl .e'p53 and t e pr ssesa n h 'm Ssmt t m 1; the e! (5 is bbld i si ala in i sr a Po iss tionl Wh n th rear nd o th p ton p s s th r r f'l i s h l bifed th Q 1 1- pression resulting acts on the face 58 o'fth' 'wl l hlch rate in ar a than the pressure surface 5 6, and moves it forward againstthe pressure'on the pressure are When h lve n its f rwa d position,airpas'ses to the, rear face of the Pi throu h P rts 3 pa ts e2 pa t heres ace o t e v lve Fa hs rea -fess o the i i o At as: ime the i in advee of h iii tefi" siexhail as antennae ,6 b ses 4 ennui: new iii th v lvblack, peas. ,8 pa n e 5 and fli iil i per ifil- Whsn th f r i and 9?the hi tqii' savers the ve a t P essure the pass ges-a and on thepressure area 56 will rise so that the pressure on the pressure e 56@Qmb iiedvit in? pre ure o th aces "5 will oisloxne he pressure man:this re as 5 an more the v lve reai- 'vard to. t e R ation h a The viion w l h be famed ear rd em' ir we ,0 l id f't a l IiOrMG t ll 66 hatWhile wen-Fe d a r s suppl ed is th fhiid chamber the pistonwillcontinue to reciprocate within the cylinder and operate the 'drillin the'manner previously described, Water is preferably supplied to theinlet the fluid chamber. .a1r 1n passing through pass ages 32 and ils 28and is conducted to the noseof'the drill by the tube23. Air which leakspast the extension 1*. of the piston mixes With the Water at the rearend of the drill and the mixture is discharged at the nose of the drill,thereby 70 facilitating the cutting action andaat the same timeS6LVll'lg.tO cleanthe hole. The

machine is lubricated with oil suppliedto the fluid chamber 31 through asmallport 31 leading to a reservoir 31''11ocatedbehind The oil mixeswith i the conducted ;to all moving parts of the machine by the air.

Many changes 1 may ebe made in 213116: details i of the constructionwithout departing "from the spirit of "heinvention andithejjnvention isnot limited to the specific .construction zhereinillustrated anddescribed.

What 1 claim is:

1. In combination in a fluid operated drill, a cylinder, a reciprocating,piston within the cylinder, a controlling "valve :for the pistonarranged at the anarlend [of the cylinder, a Naive {block in which thevalve operates secured t0 the cylinder, 1a fluid supply head arranged tothe rear of the valve block and secured thereto with a fluid chambertherebetween, a periorate drill op erated by the piston, a tubeextending from afiu d Pass ge in h h a thm h t fluid chamber to theperforation the drill and a packing means clamped abetweenthe valveblock and the head adapted to be compressed about the tube by the headand valve block to close all communication bet-ween the fluid chamberand the interior of-the tube.

2. The combination with a fluid operated drilling machine having a valveblock closing the rear end of the cylinder through whic bl k e t n a tue for upp y fluid to the drill, and a fluid supply head into whichthetube ex ends and communiy cates with the supply passage thereof adapt edto be clamped to the valve block and provided with a fluid chamberbetween the end'the alv blo k adapted to e c mp d thereby around therear portion of the tube 15 whereby communication is closed between thecylinder and thefluid' chamber, and between the fluid chamb r n the inerior of the tube and between the fluid chamber and the flu d upply Pa sg i th ea h c mbina ion th a fluid Operated drilling machine. having avalve block 0108- ing the rear end of a piston cylinder and a fluidsupply head clamped to the block with a fluid chamber therebetween andprovided w a tub for p yi g fluid t0- th drill, extending from a passagein the supply head through the fluid chamber and; the valve block, of apacking surrounding the tube within the fluid chamber and clamped be- Itween the valve block and the head whereby communication is closedbetween the cylinder and the fluid chamber, between thefluid chamberandthe interior of the tube and between the fluid chamber and the supplypassage in the head.

I 4. In combination in a fluid operated drilling machine, a cylinderhaving the rear end closed, a drill, a piston for operating the drill, afluid supply head adapted to supply fluid for operating the pistonadapted to be clamped tothe cylinder and provlde a fluid chamber betweenthe cylinder end and the head, a tube for supplying fluid to the drillhaving its rear end in communication with a fluid supply passage in thehead and extending through the fluid chamber and a hole in the rear vendof the cylinder, and a packing surrounding the tube clamped between thecylinder end and the head whereby 20 between the'fluid chamber and thefluid supply passage in the head.

' LOUIS W. GREVE.

